Comparing total chemical synthesis and total biosynthesis routes to fungal specialized metabolites.

Covering the period 1965-2024Total synthesis has been defined as the art and science of making the molecules of living Nature in the laboratory, and by extension, their analogues. At the extremes, specialised metabolites can be created by total chemical synthesis or by total biosynthesis. In this review we explore the advantages and disadvantages of these two approaches using quantitative methodology that combines measures of molecular complexity, molecular weight and fraction of sp3 centres for bioactive fungal metabolites. Total biosynthesis usually involves fewer chemical steps and those steps move more directly to the target than comparable total chemical synthesis. However, total biosynthesis currently lacks the flexibility of chemical synthesis and the ability to easily diversify synthetic routes.

Dual-Region Computed Tomography Radiomics-Based Machine Learning Predicts Subcarinal Lymph Node Metastasis in Patients with Non-small Cell Lung Cancer.

BACKGROUND: Noninvasively and accurately predicting subcarinal lymph node metastasis (SLNM) for patients with non-small cell lung cancer (NSCLC) remains challenging. This study was designed to develop and validate a tumor and subcarinal lymph nodes (tumor-SLNs) dual-region computed tomography (CT) radiomics model for predicting SLNM in NSCLC. METHODS: This retrospective study included NSCLC patients who underwent lung resection and SLNs dissection between January 2017 and December 2020. The radiomic features of the tumor and SLNs were extracted from preoperative CT, respectively. Ninety machine learning (ML) models were developed based on tumor region, SLNs region, and tumor-SLNs dual-region. The model performance was assessed by the area under the curve (AUC) and validated internally by fivefold cross-validation. RESULTS: In total, 202 patients were included in this study. ML models based on dual-region radiomics showed good performance for SLNM prediction, with a median AUC of 0.794 (range, 0.686-0.880), which was superior to those of models based on tumor region (median AUC, 0.746; range, 0.630-0.811) and SLNs region (median AUC, 0.700; range, 0.610-0.842). The ML model, which is developed by using the naive Bayes algorithm and dual-region features, had the highest AUC of 0.880 (range of cross-validation, 0.825-0.937) among all ML models. The optimal logistic regression model was inferior to the optimal ML model for predicting SLNM, with an AUC of 0.727. CONCLUSIONS: The CT radiomics showed the potential for accurately predicting SLNM in NSCLC patients. The ML model with dual-region radiomic features has better performance than the logistic regression or single-region models.

Ultrasound-based radiomics machine learning models for diagnosing cervical lymph node metastasis in patients with non-small cell lung cancer: a multicentre study.

BACKGROUND: Cervical lymph node metastasis (LNM) is an important prognostic factor for patients with non-small cell lung cancer (NSCLC). We aimed to develop and validate machine learning models that use ultrasound radiomic and descriptive semantic features to diagnose cervical LNM in patients with NSCLC. METHODS: This study included NSCLC patients who underwent neck ultrasound examination followed by cervical lymph node (LN) biopsy between January 2019 and January 2022 from three institutes. Radiomic features were extracted from the ultrasound images at the maximum cross-sectional areas of cervical LNs. Logistic regression (LR) and random forest (RF) models were developed. Model performance was assessed by the area under the curve (AUC) and accuracy, validated internally and externally by fivefold cross-validation and hold-out method, respectively. RESULTS: In total, 313 patients with a median age of 64 years were included, and 276 (88.18%) had cervical LNM. Three descriptive semantic features, including long diameter, shape, and corticomedullary boundary, were selected by multivariate analysis. Out of the 474 identified radiomic features, 9 were determined to fit the LR model, while 15 fit the RF model. The average AUCs of the semantic and radiomics models were 0.876 (range: 0.781-0.961) and 0.883 (range: 0.798-0.966), respectively. However, the average AUC was higher for the semantic-radiomics combined LR model (0.901; range: 0.862-0.927). When the RF algorithm was applied, the average AUCs of the radiomics and semantic-radiomics combined models were improved to 0.908 (range: 0.837-0.966) and 0.922 (range: 0.872-0.982), respectively. The models tested by the hold-out method had similar results, with the semantic-radiomics combined RF model achieving the highest AUC value of 0.901 (95% CI, 0.886-0.968). CONCLUSIONS: The ultrasound radiomic models showed potential for accurately diagnosing cervical LNM in patients with NSCLC when integrated with descriptive semantic features. The RF model outperformed the conventional LR model in diagnosing cervical LNM in NSCLC patients.

Increased resected lymph node stations improved survival of esophageal squamous cell carcinoma.

BACKGROUND: Neoadjuvant chemoradiotherapy (nCRT) and surgery have been recommended as the standard treatments for locally advanced esophageal squamous cell carcinoma (ESCC). In addition, nodal metastases decreased in frequency and changed in distribution after neoadjuvant therapy. This study aimed to examine the optimal strategy for lymph node dissection (LND) in patients with ESCC who underwent nCRT. METHODS: The hazard ratios (HRs) for overall survival (OS) and disease-free survival (DFS) were calculated using the Cox proportional hazard model. To determine the minimal number of LNDs (n-LNS) or least station of LNDs (e-LNS), the Chow test was used. RESULTS: In total, 333 patients were included. The estimated cut-off values for e-LNS and n-LNS were 9 and 15, respectively. A higher number of e-LNS was significantly associated with improved OS (HR: 0.90; 95% CI 0.84-0.97, P = 0.0075) and DFS (HR: 0.012; 95% CI: 0.84-0.98, P = 0.0074). The e-LNS was a significant prognostic factor in multivariate analyses. The local recurrence rate of 23.1% in high e-LNS is much lower than the results of low e-LNS (13.3%). Comparable morbidity was found in both the e-LNS and n-LND subgroups. CONCLUSION: This cohort study revealed an association between the extent of LND and overall survival, suggesting the therapeutic value of extended lymphadenectomy during esophagectomy. Therefore, more lymph node stations being sampled leads to higher survival rates among patients who receive nCRT, and standard lymphadenectomy of at least 9 stations is strongly recommended.

Perovskites as oxygen storage materials for chemical looping partial oxidation and reforming of methane.

The traditional partial oxidation, dry reforming and steam reforming of methane technologies are separated into two reactors for execution by chemical looping technology, which can avoid the defects exposed in the traditional process (avoiding carbon accumulation, reducing costs, etc.). The key to chemical looping technology is to find suitable oxygen carriers (OCs), which can store and release oxygen to form a closed loop in the chemical looping. The purpose of this review is to summarize the current status of perovskite oxides for partial oxidation and reforming of methane in chemical looping, describe the structure, oxygen capacity, oxygen migration rate and common synthesis methods of perovskites in chemical looping. In addition, the effects of impregnation loading, ion doping, and structural morphology on the catalytic conversion of CH4 by perovskite OCs and the reaction mechanism on the OCs are also discussed.

Can Omega-3 prevent the accidence of stroke: a mendelian randomization study.

BACKGROUND: The lipid-lowering effects of Omega-3 fatty acids have been widely reported, yet their impact on ischemic stroke remains controversial. Reports on the protective effects of unsaturated fatty acids, such as Omega-6 and Omega-7, as well as saturated fatty acids in cardiovascular diseases, including hypertension and ischemic stroke, are less frequent. OBJECTIVES: This study aims to identify fatty acids associated with blood pressure and ischemic stroke through Mendelian randomization. Besides, it seeks to determine whether specific fatty acids can prevent ischemic stroke by managing blood pressure and revealing the specific mechanisms of this action. METHODS: This research involved downloading relevant data from websites and extracting SNPs that met the standard criteria as instrumental variables. Simultaneously, the 'MR-PRESSO' package and 'Mendelian Randomization' package were used to eliminate confounding SNPs that could bias the study results. Then, inverse variance weighting and the weighted median were employed as primary analysis methods, accompanied by sensitivity analysis to assess the validity of the causal relationships. Initially, multivariable Mendelian randomization was used to identify fatty acids linked to blood pressure and the incidence of ischemic stroke. The causal link between certain fatty acids and the initiation of ischemic stroke was then investigated using bidirectional and mediator Mendelian randomization techniques. Stepwise Regression and the Product of Coefficients Method in mediator Mendelian randomization were utilized to ascertain whether specific fatty acids reduce ischemic stroke risk by lowering blood pressure. RESULTS: Multivariable Mendelian randomization analysis indicated a potential inverse correlation between Omega-3 intake and both blood pressure and ischemic stroke. Consequently, Omega-3 was selected as the exposure, with blood pressure and ischemic stroke-related data as outcomes, for further bidirectional and mediation Mendelian Randomization analyses. Bidirectional Mendelian Randomization revealed that Omega-3 significantly influences DBP (P = 1.01e-04) and IS (P = 0.016). It also showed that DBP and SBP significantly affect LAS, SVS, CES, IS, and LS. Mediator Mendelian Randomization identified five established mediating pathways: Omega-3-Diastolic blood pressure-Small vessel stroke, Omega-3-Diastolic blood pressure-Cardioembolic stroke, Omega-3-Diastolic blood pressure-Lacunar stroke, Omega-3-Diastolic blood pressure-Large artery atherosclerosis stroke, and Omega-3-Diastolic blood pressure-Ischemic stroke. Of these, four pathways are complete mediation, and one pathway is partial mediation. CONCLUSIONS: The findings suggest that Omega-3 may indirectly reduce the incidence of ischemic stroke by lowering blood pressure. Thus, blood pressure modulation might be one of the mechanisms through which Omega-3 prevents ischemic stroke. In summary, incorporating an increased intake of Omega-3 in the diet can serve as one of the dietary intervention strategies for patients with hypertension. Additionally, it can act as an adjunctive therapy for the prevention of ischemic strokes and their complications.

The impact of nursing interventions on the rehabilitation outcome of patients after lumbar spine surgery.

BACKGROUND: This study aimed to investigate the impact of nursing interventions on the rehabilitation outcomes of patients after lumbar spine surgery and to provide effective references for future postoperative care for patients undergoing lumbar spine surgery. METHODS: The study included two groups: a control group receiving routine care and an observation group receiving additional comprehensive nursing care. The comprehensive care encompassed postoperative rehabilitation, pain, psychological, dietary management, and discharge planning. The Visual Analogue Scale (VAS), Oswestry Disability Index (ODI), Short-Form 36 (SF-36) Health Survey, self-rating depression scale (SDS) and self-rating anxiety scale(SAS) were used to assess physiological and psychological recovery. Blood albumin, haemoglobin, neutrophil counts, white blood cell counts, red blood cell counts, inflammatory markers (IL-6, IL-10, and IFN-γ) were measured, and the incidence of postoperative adverse reactions was also recorded. RESULTS: Patients in the observation group exhibited significantly improved VAS, ODI, SF-36, SDS and SAS scores assessments post-intervention compared to the control group (P < 0.05). Moreover, levels of IL-6, IL-10, and IFN-γ were more favorable in the observation group post-intervention (P < 0.05), indicating a reduction in inflammatory response. There was no significant difference in the incidence of postoperative adverse reactions between the groups (P > 0.05), suggesting that the comprehensive nursing interventions did not increase the risk of adverse effects. CONCLUSION: Comprehensive nursing interventions have a significant impact on the postoperative recovery outcomes of patients with LSS, alleviating pain, reducing inflammation levels, and improving the overall quality of patient recovery without increasing the patient burden. Therefore, in clinical practice, it is important to focus on comprehensive nursing interventions for patients with LSS to improve their recovery outcomes and quality of life.

Machine learning model predicts airway stenosis requiring clinical intervention in patients after lung transplantation: a retrospective case-controlled study.

BACKGROUND: Patients with airway stenosis (AS) are associated with considerable morbidity and mortality after lung transplantation (LTx). This study aims to develop and validate machine learning (ML) models to predict AS requiring clinical intervention in patients after LTx. METHODS: Patients who underwent LTx between January 2017 and December 2019 were reviewed. The conventional logistic regression (LR) model was fitted by the independent risk factors which were determined by multivariate LR. The optimal ML model was determined based on 7 feature selection methods and 8 ML algorithms. Model performance was assessed by the area under the curve (AUC) and brier score, which were internally validated by the bootstrap method. RESULTS: A total of 381 LTx patients were included, and 40 (10.5%) patients developed AS. Multivariate analysis indicated that male, pulmonary arterial hypertension, and postoperative 6-min walking test were significantly associated with AS (all P < 0.001). The conventional LR model showed performance with an AUC of 0.689 and brier score of 0.091. In total, 56 ML models were developed and the optimal ML model was the model fitted using a random forest algorithm with a determination coefficient feature selection method. The optimal model exhibited the highest AUC and brier score values of 0.760 (95% confidence interval [CI], 0.666-0.864) and 0.085 (95% CI, 0.058-0.117) among all ML models, which was superior to the conventional LR model. CONCLUSIONS: The optimal ML model, which was developed by clinical characteristics, allows for the satisfactory prediction of AS in patients after LTx.

Determination of indole-3-acetic acid using disposable molecularly imprinted electrochemical sensors based on bifunctional monomers.

Stainless steel sheets were coated with carbon ink to obtain disposable carbon electrodes, which were used as supports for moleculary imprinted polymer (MIP) electrochemical sensors by electropolymerizing o-phenylenediamine and o-aminophenol along with indole-3-acetic acid (IAA) as the template. After optimization, the MIP biosensors could be used for sensitive and selective detection of IAA with the limit of quantification of 0.1 µM. Our experimental results showed that stable and reproducible electrochemical responses could be achieved for the disposable MIP biosensors. This approach was successfully used for detection of IAA in different tissues of pea sprouts. This study reveals the potential of MIP electrochemical sensors in practical applications and shrinks the trench between the research and the real world.

Molecular Iridium Catalyzed Electrochemical Formic Acid Oxidation: Mechanistic Insights.

Electrochemical formic acid oxidation reaction (FAOR) is a pivotal model for understanding organic fuel oxidation and advancing sustainable energy technologies. Here, we present mechanistic insights into a novel molecular-like iridium catalyst (Ir-N4-C) for FAOR. Our studies reveal that isolated sites facilitate a preferential dehydrogenation pathway, circumventing catalyst poisoning and exhibiting high inherent activity. In situ spectroscopic analyses elucidate that weakly adsorbed intermediates mediate the FAOR and are dynamically regulated by potential-dependent redox transitions. Theoretical and experimental investigations demonstrate a parallel mechanism involving two key intermediates with distinct pH and potential sensitivities. The rate-determining step is identified as the adsorption of formate via coupled or sequential proton-electron transfer, which aligns well with the observed kinetic properties, pH dependence, and hydrogen/deuterium isotope effects in experiments. These findings provide valuable insights into the reaction mechanism of FAOR, advancing our understanding at the molecular level and potentially guiding the design of efficient catalysts for fuel cells and electrolyzers.

CDBN-YGXZ, a Novel Small-Molecule Drug, Shows Efficacy against Clostridioides difficile Infection and Recurrence in Mouse and Hamster Infection Models.

Clostridioides difficile infection (CDI) causes severe diarrhea and colitis, leading to significant morbidity, mortality, and high medical costs worldwide. Oral vancomycin, a first-line treatment for CDI, is associated with a high risk of recurrence, necessitating novel therapies for primary and recurrent CDI. A novel small-molecule compound, CDBN-YGXZ, was synthesized by modifying the benzene ring of nitazoxanide with lauric acid. The mechanism of action of CDBN-YGXZ was validated using a pyruvate:ferredoxin/flavodoxin oxidoreductase (PFOR) inhibition assay. The efficacy of CDBN-YGXZ was evaluated using the MIC test and CDI infection model in mice and hamsters. Furthermore, metagenomics was used to reveal the underlying reasons for the effective reduction or prevention of CDI after CDBN-YGXZ treatment. The inhibitory activity against PFOR induced by CDBN-YGXZ. MIC tests showed that the in vitro activity of CDBN-YGXZ against C. difficile ranging from 0.1 to 1.5 µg/mL. In the mouse and hamster CDI models, CDBN-YGXZ provided protection during both treatment and relapse, while vancomycin treatment resulted in severe relapse and significant clinical scores. Compared with global effects on the indigenous gut microbiota induced by vancomycin, CDBN-YGXZ treatment had a mild influence on gut microbes, thus resulting in the disappearance or reduction of CDI recurrence. CDBN-YGXZ displayed potent activity against C. difficile in vitro and in vivo, reducing or preventing relapse in infected animals, which could merit further development as a potential drug candidate for treating CDI.

Metformin attenuates chronic lung allograft dysfunction: evidence in rat models.

BACKGROUND: Chronic lung allograft dysfunction (CLAD) directly causes an abysmal long-term prognosis after lung transplantation (LTx), but effective and safe drugs are not available. Metformin exhibits high therapeutic potential due to its antifibrotic and immunomodulatory effects; however, it is unclear whether metformin exerts a therapeutic effect in CLAD. We sought to investigate the effect of metformin on CLAD based on rat models. METHODS: Allogeneic LTx rats were treated with Cyclosporin A (CsA) in the first week, followed by metformin, CsA, or vehicle treatment. Syngeneic LTx rats received only vehicles. All rats were sacrificed on post-transplant week 4. Pathology of lung graft, spleen, and thymus, extent of lung fibrosis, activity of profibrotic cytokines and signaling pathway, adaptive immunity, and AMPK activity were then studied. RESULTS: Allogeneic recipients without maintenance CsA treatment manifested CLAD pathological characteristics, but these changes were not observed in rats treated with metformin. For the antifibrotic effect, metformin suppressed the fibrosis extent and profibrotic cytokine expression in lung grafts. Regarding immunomodulatory effect, metformin reduced T- and B-cell infiltration in lung grafts, spleen and thymus weights, the T- and B-cell zone areas in the spleen, and the thymic medullary area. In addition, metformin activated AMPK in lung allografts and in α-SMA+ cells and T cells in the lung grafts. CONCLUSIONS: Metformin attenuates CLAD in rat models, which could be attributed to the antifibrotic and immunomodulatory effects. AMPK activation suggests the potential molecular mechanism. Our study provides an experimental rationale for further clinical trials.

Pararespiratory and paradigestive lymph node metastases in esophageal squamous cell carcinoma: predicting survival and refining the N staging system.

BACKGROUND: The site of lymph node metastasis (LNM) may affect the prognosis of patients with esophageal squamous cell carcinoma (ESCC). To investigate the prognoses of pararespiratory and paradigestive LNM and to propose a novel N (nN) staging system that integrates both the LNM site and count. METHODS: This study was a multicenter, large-sample, retrospective cohort study that included ESCC patients with LNM between January 2014 and December 2019 from three Chinese institutes. Patients were set into training (two institutes) and external validation (one institute) cohorts. The primary outcomes were survival differences in LNM site and the development of novel nodal staging system. The overall survival (OS) of patients with pararespiratory LNM only (Group A), paradigestive LNM only (Group B), and both sites (Group C) was evaluated by Kaplan-Meier. Cox proportional hazards models were used to identify the independent prognostic factors. An nN staging system considering both the LNM site and count was developed and evaluated by the area under the receiver operating characteristic curve (AUC). RESULTS: In total, 1313 patients were included and split into training (n = 1033) and external validation (n = 280) cohorts. There were 342 (26.0%), 568 (43.3%) and 403 (30.7%) patients in groups A, B and C, respectively. The OS of patients with pararespiratory and patients with paradigestive LNM presented significant differences in the training and validation cohorts (P < 0.050). In the training cohort, LNM site was an independent prognostic factor (hazard ratio: 1.58, 95% confidence intervals: 1.41-1.77, P < 0.001). The nN staging definition: nN1 (1-2 positive pararespiratory/paradigestive LNs), nN2 (3-6 pararespiratory LNs or 1 pararespiratory with 1paradigestive LN), nN3 (3-6 LNs with ≥ 1 paradigestive LN), nN4 (≥ 7 LNs). Subsets of patients with different nN stages showed significant differences in OS (P < 0.050). The prognostic model of the nN staging system presented higher performance in the training and validation cohorts at 3-year OS (AUC, 0.725 and 0.751, respectively) and 5-year OS (AUC, 0.740 and 0.793, respectively) than the current N staging systems. CONCLUSIONS: Compared to pararespiratory LNM, the presence of paradigestive LNM is associated with worse OS. The nN staging system revealed superior prognostic ability than current N staging systems.

Construction and validation of a predictive model for postoperative urinary retention after lumbar interbody fusion surgery.

BACKGROUND: Postoperative urine retention (POUR) after lumbar interbody fusion surgery may lead to recatheterization and prolonged hospitalization. In this study, a predictive model was constructed and validated. The objective was to provide a nomogram for estimating the risk of POUR and then reducing the incidence. METHODS: A total of 423 cases of lumbar fusion surgery were included; 65 of these cases developed POUR, an incidence of 15.4%. The dataset is divided into a training set and a validation set according to time. 18 candidate variables were selected. The candidate variables were screened through LASSO regression. The stepwise regression and random forest analysis were then conducted to construct the predictive model and draw a nomogram. The area under the curve (AUC) of the receiver operating characteristic (ROC) curve and the calibration curve were used to evaluate the predictive effect of the model. RESULTS: The best lambda value in LASSO was 0.025082; according to this, five significant variables were screened, including age, smoking history, surgical method, operative time, and visual analog scale (VAS) score of postoperative low back pain. A predictive model containing four variables was constructed by stepwise regression. The variables included age (ß = 0.047, OR = 1.048), smoking history (ß = 1.950, OR = 7.031), operative time (ß = 0.022, OR = 1.022), and postoperative VAS score of low back pain (ß = 2.554, OR = 12.858). A nomogram was drawn based on the results. The AUC of the ROC curve of the training set was 0.891, the validation set was 0.854 in the stepwise regression model. The calibration curves of the training set and validation set are in good agreement with the actual curves, showing that the stepwise regression model has good prediction ability. The AUC of the training set was 0.996, and that of the verification set was 0.856 in the random forest model. CONCLUSION: This study developed and internally validated a new nomogram and a random forest model for predicting the risk of POUR after lumbar interbody fusion surgery. Both of the nomogram and the random forest model have high accuracy in this study.

Ultrasound-based advanced oxidation processes for landfill leachate treatment: Energy consumption, influences, mechanisms and perspectives.

Advanced oxidation processes (AOPs) based on ultrasound (US) have attracted considerable attention in recent years due to its advantages in the degradation of landfill leachate. The review summarizes the existing treatment methods of leachate from lab-scale, compares their advantages and disadvantages by focusing on the degradation of emerging contaminants (ECs) in the leachate. Then the US-based AOPs are introduced emphatically, including their degradation mechanisms, influencing factors, energy consumption, further optimization methods as well as the possibility of field-scale application are systematically described. Moreover, this review also expounds on the advantages of dual-frequency US (DFUS) technology compared with single-frequency US, and a theoretically feasible DFUS process is proposed to treat ECs in the leachate. Finally, suggestions and prospects for US technologies in treating landfill leachate are put forward to aid future research on landfill leachate treatment. Meaningfully, this manuscript will provide reference values of US-based technologies in landfill leachate treatment for the practical use, facilitating the development of US-based AOPs in landfill leachate management and disposal.

Double-lung versus heart-lung transplantation for end-stage cardiopulmonary disease: a systematic review and meta-analysis.

We compared posttransplant outcomes following double-lung transplantation (DLTx) and heart-lung transplantation (HLTx), based on a search of PubMed, Cochrane Library, and Embase, from inception to March 8, 2022, for studies that report outcomes of these procedures. We then performed a meta-analysis of baseline characteristics and posttransplant outcomes. Subgroup analyses were implemented according to indication, publication year, and center. This study was registered on PROSPERO (number CRD42020223493). Ten studies were included in this meta-analysis, involving 1230 DLTx patients and 1022 HLTx patients. The DLTx group was characterized by older donors (P = 0.04) and a longer allograft ischemia time (P < 0.001) than the HLTx group. The two groups had comparable 1-year, 3-year, 5-year, 10-year survival rates (all P > 0.05), with similar results identified in subgroup analyses. We found no significant differences in 1-year, 5-year, and 10-year chronic lung allograft dysfunction (CLAD)-free survival, length of intensive care unit stay and hospital stay, length of postoperative ventilation, in-hospital mortality, or surgical complications between the groups (all P > 0.05). Thus, DLTx provides similar posttransplant survival to HLTx for end-stage cardiopulmonary disease. These two procedures have a comparable risk of CLAD and other posttransplant outcomes.

Correlation between Elbow Flexor Muscle Strength and Needle Electromyography Parameters after Musculocutaneous Nerve Injury.

OBJECTIVES: To explore the changes of elbow flexor muscle strength after musculocutaneous nerve injury and its correlation with needle electromyography (nEMG) parameters. METHODS: Thirty cases of elbow flexor weakness caused by unilateral brachial plexus injury (involving musculocutaneous nerve) were collected. The elbow flexor muscle strength was evaluated by manual muscle test (MMT) based on Lovett Scale. All subjects were divided into Group A (grade 1 and grade 2, 16 cases) and Group B (grade 3 and grade 4, 14 cases) according to their elbow flexor muscle strength of injured side. The biceps brachii of the injured side and the healthy side were examined by nEMG. The latency and amplitude of the compound muscle action potential (CMAP) were recorded. The type of recruitment response, the mean number of turns and the mean amplitude of recruitment potential were recorded when the subjects performed maximal voluntary contraction. The quantitative elbow flexor muscle strength was measured by portable microFET 2 Manual Muscle Tester. The percentage of residual elbow flexor muscle strength (the ratio of quantitative muscle strength of the injured side to the healthy side) was calculated. The differences of nEMG parameters, quantitative muscle strength and residual elbow flexor muscle strength between the two groups and between the injured side and the healthy side were compared. The correlation between elbow flexor manual muscle strength classification, quantitative muscle strength and nEMG parameters was analyzed. RESULTS: After musculocutaneous nerve injury, the percentage of residual elbow flexor muscle strength in Group B was 23.43% and that in Group A was 4.13%. Elbow flexor manual muscle strength classification was significantly correlated with the type of recruitment response, and the correlation coefficient was 0.886 (P<0.05). The quantitative elbow flexor muscle strength was correlated with the latency and amplitude of CMAP, the mean number of turns and the mean amplitude of recruitment potential, and the correlation coefficients were -0.528, 0.588, 0.465 and 0.426 (P<0.05), respectively. CONCLUSIONS: The percentage of residual elbow flexor muscle strength can be used as the basis of muscle strength classification, and the comprehensive application of nEMG parameters can be used to infer quantitative elbow flexor muscle strength.

Polymelamine Formaldehyde-Coated MIL-101 as an Efficient Dual-Functional Core-Shell Composite to Catalyze the Deacetalization-Knoevenagel Tandem Reaction.

Porous organic polymer (POP) coated on a metal-organic framework (MOF) has the functions and advantages of MOF and POP at the same time and has excellent catalytic ability. In this study, an efficient dual-functional core-shell composite MOF@POP with Lewis acid and Brønsted base sites was synthesized using the impregnation method in which MIL-101(Cr) was the core component and polymelamine formaldehyde (PMF) was the shell component. Most importantly, the obtained MIL-101(Cr)@PMF showed perfect catalytic activity in the deacetalization-Knoevenagel tandem reaction. In addition, it could still maintain ultrahigh physical and chemical stability.

Evolution law of comet-shaped defects in magnetorheological finishing.

Ultraprecision optical systems such as high-energy laser systems have very strict requirements for surface defects of optical components. Comet-shaped defects are common in magnetorheological finishing, which is one of the main ultraprecision manufacturing technologies. Computational fluid dynamics is used to simulate the pressure and velocity of the magnetorheological fluid in pits during magnetorheological finishing for the first time, to the best of our knowledge. The simulation model analyzes the distribution of velocity and pressure in the process of the formation of comet-shaped defects. After the simulation, magnetorheological polishing experiments were carried out on the fused quartz silica glass. The polishing experiments use the rotation speed and immersion depth of the polishing wheel to verify the velocity and pressure distribution in the simulation experiment. The polishing experiment results are consistent with the simulation results, which show that the high polishing speed will increase the depth of the defect, and the uneven velocity and pressure distribution at the pits make the pits evolve into comet-shaped defects. We explain the cause of comet-shaped defects from the perspective of material removal and provide an optimization method of process parameters for high-efficiency removal of comet-shaped defects.

Copper accumulation and physiological markers of soybean (Glycine max) grown in agricultural soil amended with copper nanoparticles.

Copper-based nanoparticles (NPs) display a strong potential to replace copper salts (e.g., CuSO4) for application in agricultures as antimicrobial agents or nutritional amendments. Yet, their effects on crop quality are still not comprehensively understood. In this study, the Cu contents in soybeans grown in soils amended with Cu NPs and CuSO4 at 100-500 mg Cu/kg and the subsequent effects on the plant physiological markers were determined. The Cu NPs induced 29-89% at the flowering stage (on Day 40) and 100-165% at maturation stage (on Day 100) more Cu accumulation in soybeans than CuSO4. The presence of particle aggregates in the root cells with deformation upon the Cu NP exposure was observed by transmission electron microscopy. The Cu NPs at 100 and 200 mg/kg significantly improved the plant height and biomass, yet significantly inhibited at 500 mg/kg, compared to the control. In leaves chlorophyll-b was more sensitive than chlorophyll-a and carotenoids to the Cu NP effect. The Cu NPs significantly decreased the root nitrogen and phosphorus contents, while they significantly increased the leaf potassium content in comparison with control. Our results imply that cautious use of Cu NPs in agriculture is warranted due to relatively high uptake of Cu and altered nutrient quality in soybeans.